The specific goal of this project is production of commercial-scale quantities of the anti- tumor compound halomon via cultivation of the only known source, the marine alga Portieia hornemannii in a custom new photobioreactor (Algal Pharm). Phase I will test the feasibility of producing algal biomass and the natural product halomon in 85 L modular photobioreactors. Culture manipulations based on the physiological and chemical ecology of the alga will also be tried in Phase I leading to Phase II goals for designing, testing and optimization of pilot- scale commercial culture for halomon production to meet the needs of clinical development.